1. Field of the Invention
The present invention relates to a screen printing apparatus, and more particularly to a screen printing apparatus which is structured such that a printing operation and a checking and inspecting operation of a print state can be performed in a flow work.
2. Description of the Prior Art
A substrate such as a printed circuit board is fed to a next mounting step after a printing agent such as a creamed solder or the like is applied in a predetermined pattern by a screen printing apparatus, and electronic parts are mounted thereon.
However, if an accurately right printing is not applied in the printing step in accordance with a predetermined pattern, the substrate on which the electronic parts are mounted becomes inferior. Accordingly, a checking and inspecting operation of the print state is performed at a time when the printing is finished.
Then, the checking and inspecting operation is conventionally performed after moving the substrate to another test machine after the printing is finished. Accordingly, a loss time is generated and a whole work flow is deteriorated.
The present invention is made by taking the points mentioned above into consideration, and an object of the present invention is to provide a screen printing apparatus which is structured such that a printing operation and a checking and inspecting operation of a print state can be performed in a flow work.
Then, in accordance with a gist of the present invention, there is provided a screen printing apparatus comprising:
a mask frame;
a camera apparatus for a checking and inspecting operation of a print state in a substrate, the camera apparatus being arranged in parallel to the mask frame along a direction of transferring the substrate and capable of moving in a transfer direction of the substrate and a direction perpendicular to the transfer direction;
a squeegee apparatus having a fixed support plate arranged above the mask frame, a squeegee support plate mounted to the fixed support plate and moving along the transfer direction of the substrate at a proper timing, and a squeegee mounted to the squeegee support plate and vertically moving at a proper timing; and
a substrate supporting table arranged below the mask frame and the camera apparatus for the check and inspection of the print state in the substrate, capable of moving in the transfer direction of the substrate and the direction perpendicular to the transfer direction and capable of vertically moving and rotating in a horizontal direction.
Further, the structure is made such that the camera apparatus for the check and inspection of the print state in the substrate is constituted by an irradiating apparatus structured such that a light emitting body comprising a light emitting diode (LED) is arranged so as to direct in an opposite side to the substrate and covered with a semispherical cap, on the top portion of which a photographing hole having a predetermined diameter is provided and on an inner surface of which a light reflection is suitably restricted, thereby a light of the light emitting body irradiating on the substrate after reflecting on the inner surface of the semispherical cap, and by a charge coupled device (CCD) camera arranged above the irradiating apparatus. Accordingly, since the light of the light emitting body can be irradiated softly by an indirect lighting, and a halation is not generated, it is possible to accurately photograph the print state by the CCD camera. Therefore, it is possible to accurately check and inspect the print state.